Pressure-cooking appliances of the pressure cooker type are already known that are provided with opening safety means. Such opening safety means are well known per se. They make it possible for positive opening safety to be provided by allowing the lid of the appliance to be released relative to the bowl only when the pressure level prevailing inside the vessel reaches a level acceptable from the point of view of user safety, i.e. a pressure level that is low enough to avoid any sudden expulsion of the lid or any spraying of scalding-hot cooking substances.
Such known opening safety means are generally constituted by a pressure-gauge rod that is sensitive to the pressure prevailing inside the cooking vessel, and that is mounted to move between a low position in which it allows the lid to be unlocked, and a high position, in which it co-operates with the locking/unlocking means for locking/unlocking the lid in a manner such as to prevent said means from going from the locking position to the unlocking position.
In such known appliances, the pressure-gauge rod moves upwards and downwards automatically and as a function of the pressure prevailing inside the cooking vessel only. The pressure-gauge rod in such a prior art appliance also has a weight/size compromise calculated to be favorable to the rod moving upwards into its high position early, e.g. as soon as the pressure inside the pressure cooker reaches or exceeds 0.5 kilopascals (kPa).
Early upward movement of the rod is desirable in order to enable the pressure to increase as quickly as possible, which is not possible so long as the pressure-gauge rod is in the low position, which is a non-leaktight position.
Unfortunately, even when the rod is ideally shaped and dimensioned to be favorable to said rod rising into its high position early, it is observed, in practice, that it is generally necessary to subject the appliance to a heat source having high power in order to ensure that the rod does indeed rise “early”.
In addition, if the weight/size compromise of the known pressure-gauge rods is chosen to be favorable to early rising of the rod, the same compromise is unfavorable to the rod moving downwards from its high position to its low position. In practice, it is observed that, in particular due to the very small weight of the rod, which weight is chosen to be favorable to the rod rising, the rod moving downwards is often random, and, in any event, takes place at a pressure that is generally considerably lower than the pressure that caused it to rise.
Therefore, the user must generally wait for a relatively long time between the moment at which the user triggers decompression of the appliance, and the moment at which the user can actually separate the lid from the bowl, in order to access the food.
Such a relatively long time also prevents a pressure cooker from being used as a conventional cooking pot, with which the user can very easily and quickly open and close the lid at will during cooking, for the purposes of inspecting the food directly, of seasoning it, or of tasting it, for example.
The opening safety means equipping known cooking means thus considerably slow down the overall time of the cooking cycle, by requiring a latency time at the beginning and at the end of cooking.